var _t;
var _delay = 4 * 1000;
var _currentBanner = 1;

function cacheImages() {
    var img;
    img = new Image();
    img.src = '/i/img/home/banner-bg-green.jpg';
    img = new Image();
    img.src = '/i/img/home/banner-bg-red.jpg';
    img = new Image();
    img.src = '/i/img/home/banner-bg-orange.jpg';
}

function stopBannerRotation() {
    clearTimeout(_t);
}

function resumeBannerRotation() {
    _t = setTimeout('swapBanners()', _delay);
}

function swapBanners() {
    var n = _currentBanner;
    n++;
    if (n > 4) n = 1;
    showBanner(n);
    resumeBannerRotation();
}

function showBanner(bannerNum) {
    var banner;
    var ribbon;
    var bgOffset;
    stopBannerRotation()
    _currentBanner = bannerNum;
    for (var n = 1; n <= 4; n++) {
        banner = $('#home-banner-'.concat(n));
        ribbon = $('#home-ribbon-'.concat(n));
        bgOffset = 236 * (n - 1) + 1;
        if (n == bannerNum) {
            banner.attr({ style: 'display: block' });
            ribbon.attr({ style: 'background-position: -' + bgOffset + 'px -138px' });
        }
        else {
            banner.attr({ style: 'display: none' });
            ribbon.attr({ style: 'background-position: -' + bgOffset + 'px 0px' });
        }
    }
}

$(document).ready(function() {
    resumeBannerRotation();
    cacheImages();
});